15针VGA显示接口引脚定义
VGA 是 Video Graphics Adapter(Array) 的缩写，信号类型为模拟类型，显示卡端的接口为 15 针母插座：
Pin Name Description Pin Name Description 1 RED Red Video (75 ohm, 0.7 V p-p) 9 KEY Key (No pin) 2 GREEN Green Video (75 ohm, 0.7 V p-p) 10 SGND Sync Ground 3 BLUE Blue Video (75 ohm, 0.7 V p-p) 11 ID0 Monitor ID Bit 0 4 ID2 Monitor ID Bit 2 12 Monitor ID Bit 1 5 GND Ground 13 HSYNC or CSYNC Horizontal Sync (or Composite Sync) 6 RGND Red Ground 14 VSYNC Vertical Sync 7 GGND Green Ground 15 ID3 or SCL Monitor ID Bit 3 8 BGND Blue Ground